Matrix clock



FIG. 1 is a top, left front perspective view of a first embodiment of a matrix clock showing our new design;

FIG. 2 is a front elevational view thereof;

FIG. 3 is a top, left front perspective view of a second embodiment of our design of FIG. 1;

FIG. 4 is a front elevational view of FIG. 3;

FIG. 5 is a top, left front perspective view of a third embodiment of our design of FIG. 1;

FIG. 6 is a front elevational view of FIG. 5;

FIG. 7 is a top, left front perspective view of a fourth embodiment of our design of FIG. 1; and,

FIG. 8 is a front elevational view of FIG. 7. 

CLAIM The ornamental design for a matrix clock, as shown and described. 